1. Field of Invention
Embodiments of the invention relate generally to electronic devices and, more specifically, in certain embodiments, to electronic devices having local data lines.
2. Description of Related Art
In some memory devices, a storage device, such as a capacitor, communicates with a sense amplifier through a data line, e.g., a digit line. Typically, the capacitor stores data with its charge state, e.g., a charged capacitor may represent a logic value of “1,” and an uncharged capacitor may represent a logic value of “0.” To read data from the capacitor, a switch between the capacitor and the data line is closed, and electrons flow between the capacitor and the data line, thereby changing the voltage of the data line. This change in the voltage is typically registered by the sense amplifier, which may categorize the change in voltage as indicating either that the capacitor is storing a 0 or that the capacitor is storing a 1.
Often, the data lines have a relatively large capacitance compared to the capacitor storing data. In some designs, a single-data line may service a plurality of capacitors. These data lines may be relatively long, extending in some designs across an entire block of memory. Along their length, the data lines may capacitively couple to other conductors that are at different voltages, conductors such as other data lines. This capacitive coupling is referred to as “parasitic capacitance,” and it can slow the operation of the memory device. Parasitic capacitance is known to slow the rate at which the capacitor storing data changes the data line voltage, thereby increasing the amount of time it takes to read data from the capacitor.